Solid phase stepwise synthesis has become a ubiquitous technique for the preparation of various oligomeric or polymeric molecules, such as oligonucleotides and oligonucleotide analogs, peptides, peptoids, and oligosaccharides. Frequently, the molecules are biologically active or are candidates for a biological activity. The technique is valued for its high efficiency, allows preparation of diverse arrays or libraries of molecules, which may remain bound to the solid support, and is readily amenable to automation.
In many cases, it is desirable to conjugate the molecules to other molecular moieties, such as other biomolecules (e.g. peptoids linked to oligonucleotides), masked linking groups, or spacer groups. Such conjugation may require solution phase reaction or time consuming modifications to otherwise automated syntheses. Therefore, it would be useful to provide methods of such conjugation that can be carried out entirely in the solid phase, with minimal disruption to automated synthetic protocols.